The imaging needs of the scientific projects will rely upon the instruments and expertise of the UMMS Biomedical Imaging Group, a long established and productive group of researchers who have contributed significantly to recent advances in the fluorescence imaging of living cells. The group?s laboratory is located in the same building as the other laboratories of the proposed PPG, and its instruments and investigators provide unique capabilities for the 3-d imaging, analysis and display of distributions of fluorescent molecules in fixed and living cells. The four faculty members will provide Program Project investigators with expertise in: the design of imaging experiments, including equipment modifications; image restoration of their 3-d data sets for highest spatial resolution; and the quantitative analysis and effective display of their data. The faculty and technical staff are experts in all aspects of modern light microscopy, have developed the instruments and software tools to be used in these investigations, and will make any necessary changes to the hardware, processing algorithms, and data analysis protocols required to successfully complete the imaging for this PPG The primary instruments and computer hardware and software to be used are: - A digital imaging fluorescence microscope (DIM) capable of producing high resolution 3-d images of fluorophore distributions in fixed and living cells using an image restoration algorithm developed at UMMS. - A laser illuminated high-speed DIM, with a unique multi-output CCD camera, capable of acquiring 540 2-d or 90 3-d images per second. This system provides unique capabilities for 3-d time series imaging of cellular processes in living cells, such as diffusion or motor driven transport, - A network of Silicon Graphics workstations running specialized display and analysis software, developed at UMMS, which provides capabilities for analysis of temporal dynamics and the quantification of protein co-localization, including the analysis of fluorescence resonance energy transfer (FRET).